Alkylation process



Patented Dec. 14, 1948 ALKYLATION PROCESS Maryan P. Matuszak,Bartlesville, Okla... assignor to Phillips Petroleum Company, acorporation of Delaware Application August 6,1945, Serial No. 609,214

20 Claims. (Cl. 260-845) This invention relates to an alkylation processand more particularly to an improved process for reacting a low-boilingaliphatic olefin with an alkylatable cyclic organic compound to producealkyl derivatives thereof wherein hydrogen atoms on the ring arereplaced by alkyl groups corresponding to the olefin. Still moreparticularly it relates to a process for the alkylation of benzene,toluene or other aromatic compound, furan, derivatives of furan,cycloparaffins, and any other cyclic organic compounds which are capableof being alkylated vby replacement of hydrogen on the ring with alkylgroups.

This application is a continuation-in-part of my prior and copendingapplication, Ser. No. 467,874, filed December 4, 1942, now Patent No.2,387,162.

In present-day acid-catalyzed alkylation processes, it is necessary, forobtaining optimum results, to limit the proportions of inert diluents inthe feed to the alkylating zone. Diluents in the feed reduce the maximumproduction capacity of alkylating equipment and, if present in highproportion, cause reductions in yield and quality of the product.Although diluents are sometimes removed from feeds by preliminaryfractional distillation, such distillation in many instances.is noteconomically feasible, particularly in the utilization of olefinicstreams that contain only a few per cent of olefin. The present processadvantageously efiects removal of inerts without such preliminarydistillation.

The principal object of the present invention is to provide an improvedprocess for the alkylation of an alkylatable cyclic organic compoundwith a low-boiling aliphatic olefin. Another object is to provide such aprocess for the alkylation of aromatic hydrocarbons. Another object isto provide such a process for the alkylation of a so-calledsuperaromatic such as furan. Another object is to provide such a processwherein the olefin employed is in admixture with large proportions ofinert materials especially the corresponding paraflin. Another object isto provide such a process wherein the olefin is an isoolefin such asisobutylene and is in admixture with large proportions of thecorresponding isoparafiin such as isobutane, as for example, in the casewhere the olefin-containing feed is prepared by the catalyticdehydrogenation of isobutane followed by known treatment to segregatethe C4 fraction. Another object is to minimize the alkylation ofisoparafiin in a process of the type mentioned in the preceding sentencewhereby consumption of olefin by alkylation of isoparaflln is kept at aminimum and a maximum of the olefin contained in the feed is convertedto the desired principal product, namely, alkylate of the cyclic organiccompound. Another object is to provide a process as just outlinedwherein the isoparafiin present in the feed is eliminated ahead of thealkylation zone wherein alkylation of the cyclic organic compound takesplace, said elimination removing both the isoparamn present as such andthe small proportion thereof which is inevitably alkylated prior to thealkylation zone proper. Another object is to provide a process as in theforegoing wherein the by-product higher isoparaffln, usually isooctane,formed by unavoidable alkylation of isoparaflin prior to the mainalkylation zone is separately recovered in a novel and advantageousmanner. Another object is to provide a process which accomplishes theforegoing objects in a simple, economical manner requiring a minimum ofcontrol and which is readily controlled to effect the desired results toan optimum extent.

Many other aims, objects and advantages of the present invention will beapparent to those skilled in the art from this description taken inconjunction with the accompanying drawing which portraysdiagrammatically one arrangement of equipment which has been found verysuitable for carrying out the present invention in an embodiment thereofwherein benzene is alkylated.

General In one aspect, the present invention involves a process forreacting a low-boiling aliphatic olefin, and especially the C: to C6olefins, namely, propylene, any of the three butylenes, and any of thepentenes, with an alkylatable cyclic organic compound, especiallyaromatic hydrocarbons and furan, to eifect replacement of hydrogen atomson the ring with alkyl groups corresponding to the olefin by intimatelyadmixing the olefincontaining hydrocarbon material which almostinvariably contains large proportions of the corresponding parafiln withliquid concentrated hydrofluoric acid in amount substantially equimolarto the olefin, maintaining the resulting mixture under conditionseffecting substantially complete hydrofiuorination of the olefin contentas substantially the sole reaction, 1. e., to the substantial exclusionof alkylation of any isoparafiln present in the feed, extracting theresulting mixture with sufficient added liquid concentrated hydrofluoricacid to form a separate liquid acid phase under conditions such thatsubstantially complete extraction of the alkyl fluorides in saidliquidhy'drofluoricacid j sult, separating the resulting extract fromthe v raflinatewhich contains the, paraflln and anyv f- "small amount ofalkylate formed by alkylati-an of a small. amount of any isoparaflin.present concomltantly,wlth'the extraction, directly admixing r theextract with a molar excess of the alkylatable cyclic organic compoundand subjecting the re- I suiting mixture to conditions efl'ectingalkylation of the cyclic organic compound with substanti'allyall of thealkyl fluorides, and recovering the allgvl derivatives so produced asthe product-of the process.

phase the principal re- In one specific embodiment, this invention is animprovedprocess for reacting a low-boiling olefin and benzene to producean alkylate in the presence of hydrofluoric acid, which comprisesintlmately admixing with a hydrocarbon material containing a low-boilingolefin hydrofluoric acid in a proportion substantially equimolecular tothe olefin, maintaining the resulting mixture for not more than about 30minutes, extracting said mixture with substantially anhydrous liquidhydrofluoric acid in an extraction step at an extraction temperature notgreater than about 100 F., mixing with the resulting extract benzene inan alkylation zone under conditions such as to produce an alkylate,separating the eflluent from said alkylation zone into a relativelylight phase and arelatlvely heavy hydrofluoric acid phase, recoveringsaid alkylate from said light phase, passing a major portion of saidacid phase to said extraction step as a part of the extraction solvent,passing the raifinate from said extraction step to a-distillation stepfor recovery of dissolved hydrofiuoric acid therefrom, passing a minorportion of -sald acid phase to said distillation step for removal oforganic impurities, and passing purified and recovered hydrofluoric acidfrom said distillation step to said extraction step.

Compounds alkylated Any cyclic organic compound which is alkylatablewith a low-boiling olefin in the presence of liquid substantiallyanhydrous hydrofluoric acid may be employed in carrying out the presentinvention. Ordinarily I alkylate either an aromatic hydrocarbonespecially the normally monocycllc aromatics such as benzene, toluene,xylene, cumene, mesitylene, ethylbenzene, etc., or a socalledsuperaromatic" such as furan. Instead of furan, its. alkylatablehomologs and derivatives may be used such as Z-furoic acid, methyl 2-furoate, 2-furyl-phenyl-ketone and the like. Furan is more easilyalkylated than benzene and other alkylatable aromatics although it has asmaller number of replaceable hydrogen atoms per molecule. Similaralkylatable compounds, which in part may be characterized as having atleast two conjugated double bonds in a ring, may be employed, examplesbeing phenol, pyrrol, thiophene and homologs, but usually benzene andits homolog's or furan is to be preferred.

Olefin-containing material I may use any aliphatic olefin-containingmaterial whlchcontains any of the low-boiling olefins in admixture witha substantial proportion of diluent hydrocarbon so that separation byfracvention obviates such preliminary separation since the diluent whichis generally low-boiling awn although hydrogen may also be present,

is rejected as the raflinate'in the extraction step which follows thehydrofiuorination. Very often the diluent is the paraflin correspondingto the olefin. Hydrogen and methane have usually been removed by'theusual means. The olefin is com- {monly a C: to C5 olefin or mixture ofsuch olefins. Since alkylation of isoparaillns with ethyl fluoride withanhydrous hydrogen fluoride as the catalyst is somewhat more difficultthan in the case of propyl fluoride and the higher alkyl 1 fluorides,the C3 or higher oleflns are often preferred. Since C6 streams are oftenmore valuable for other purposes, a C3 and/or C4 stream is morefrequently employed in carrying out the present invention. A feedcontaining isobutylene and isobutene is very advantageously employed inthe process of the present invention, the isobutylene giving'valuabletertiary butyl derivatives and the isobutane being alkylated to only alimited extent in the hydrofluorination and alkylation steps of theinvention and being rejected in the rafflnate in the extraction step.The olefin-containing stream may be derived from any suitable source.Generally, it is prepared either by cracking or by dehydrogenation of asuitable feed stock such as crude oil, gas oil, naphtha, thecorresponding paraflln, etc. It may be a by-product or the principalproduct of the cracking operation. Generally, undesired heavier andlighter materials are removed prior to the process of the presentinvention. For example, fixed gases such as hydrogen and methane arereadily removed in the conventional manner and materials heavier thanthe desired olefin, such as tars, etc, are likewise easily removed.Preferably the olefin-containing feed is free from sulfur, oxygen andnitrogen compounds including mercaptan and hydrogen sulfide as well aselementary sulfur, since the presence of such compounds in the processordinarily is undesirable.

The olefin-containing feed usually contains large proportions of thecorresponding paraflin or parafflns. Generally, the feed will containover 50% of parafiln and often more than thereof ranging up to or even99%, the balance being olefin. It is a major advantage of the presentinvention that such dilute streams can be employed even in the casewhere an isoparaflin is present, since such isoparaflln is but littlealkylated so that a maximum of the olefin is converted to the desiredproduct, namely, the alkylated cyclic organic compound. Any isoparaflinthat is alkylated is converted to highly branched higher isoparaifinHudrofluorinatirm step In this step the olefin-containing feed isintimately admixed with substantially anhydrous liquid HF in an amountsubstantially stoichiometrically equal to the olefin and the mixture issubjected to reaction conditions efiecting hydrofluorination ofsubstantially all the olefin as substantially the sole reaction. Thetemperature may be in the range of 40 to 200 F. and preferably below F.The pressure should be such as to maintain the hydrocarbonspredominantly in-liquld phaseand may range from 100 to 300 pounds gage.The mol proportion of HF to olefin should preferably be within the rangeof from 1 to 1.1 times the total olefin. At proportions much'above thisrange polymerization of Extraction step The reaction mixture leaving thehydrofluorination zone and consisting essentially of alkyl fluoride andthe inerts. usually essentially paraffln-ic, is extracted withsubstantially anhydrous liquid hydrofluoric acid in amount sufficient toform a separate liquid phase sufliciently large to dissolvesubstantially all of the alkyl fluoride.

The volume of hydrofluoric acid used should be equivalent in mols toabout -20 or more times the number of mols of the alkyl fluoridespresent. Lesser proportions are likely to result in incompleteextraction of alkyl fluorides whereas greater proportions place anunnecessarily large quantity of hydrofluoric acid in circulation in thesystem and cause an excessive consumption of alkyl fluorides byalkylation of isoparaflln where present. The conditions of theextraction step are such that liquid-liquid extraction is accomplished,the hydrocarbon phase and the hydrofluoric acid phase being intimatelymixedor emulsified with one another followed by a separation of therafflnate phase containing the inert components including anyisoparaflin and the extract phase in a conventional manner. The time ofcontacting may range from seconds to 5 minutes. The shorter thecontacting the better is the result as long as intimate contacting ofacid and hydro- Alkulation step The extractfrom the extraction step ispassed to an alkylation zone to which is also supplied carbon isattained. When the time is excessively objectionable side reactions.

I have found that the extraction may be very satisfactorily conductedwith the amount of separate liquid hydrofluoric acid phase ranging fromapproximately 0.2 to 0J3 times the volume of the hydrocarbon phase. Bylimiting the amount of separate liquid hydrofluoric acid phase in theextraction step, alkylation of the isopara'flin derived from the olefincontaining feed is kept at a desirable minimum;

The rafiinate from the extraction step is ordinarily passed to afractionation step wherein the hydrofluoric acid contained therein isrecovered as an overhead for recycle to the extraction step from abottoms product containing inert material. Where isoparaflin is presentin the feed and alkylation thereof to any substantial extent takes placein the hydrofluorination and/or extraction step, the resulting higherisoparamn may be recovered by fractional distillation of the rafllnate.

the cyclic organic compound which is to be alkylated in accordance withthe present invention. The reaction conditions in the alkylation zoneare well known to those skilled in the art of hydrofluoric acidalkylation and may comprise a temperature in the range of -20 to 200 F.,sufllcient pressure to maintain liquid phase, an average reaction timein the range of from 1 to minutes. good agitation, a mol ratio of cyclicorganic compound to alkyl fluoride of from 1.5 to 10 or more, a ratio offrom 5 to 10 being preferred, and a hydrocarbon-to-catalyst volume ratioin the range of from 0.2 to 4. Ordinarily the conditions of thealkylation are so adjusted that the mono-alkyl derivatives of the cyclicorganic compound is the predominant or nearly the entire (say at least00%) alkylated product of the alkylation reaction, since generally thepolyalkyl derivatives are not as desirable as the monoalkyl compounds.Any of the usual contacting devices commonly employed in alkylation maybe employed. The alkylation eliluent is allowed to separate by gravityor other means into two liquid phases, namely, a lighter organic phasecontaining the desired alkylated organic compound and a heavier acidphase. The organic phase is treated in any suitable manner usually byfractionation to recover the alkylated organic compound as the productof the process. Any hydrofluoric acid dissolved therein may also berecovered or recycled to the extraction step. The acid phase ispreferably in part recycled to the extraction step and in part passed tothe same fractionation column wherein the railinate described above isdistilled. In this way the hydrogen fluoride is recovered as an overheadfor recycle to the extraction step from a bottoms product containing inaddition to the inert compounds derived from the rafflnate theacid-soluble oils contained in the acid phase.

Drawing Referring to the accompanying drawing the olefin containing feedand substantially pure hydrofluoric acid are fed via lines I and 2,respectively, to mixer 3. The mixture is held in time tank 4 for thenecessary period of time to accomplish hydrofluorination of olefin. Theresulting mixture is then passed into extractor 5 where it isliquid-liquid extracted with liquid by drofluoric acid introduced byline 6. The rainnate passes via lines 1 and 8 to column 9 or, whereisoparaflin alkylation takes place to limited extent, via line I0 intothe column II which separates it into an overhead of hydrofluoric acidand isobutane which may be recycled via lines l2 and I3 and a bottomsproduct containing the isoparaffin alkylate withdrawn via line l4.

The extract separated in extractor 5 is passed via line IS, with addedHF introduced via line It if desired, to alkylator 'I'l where thealkylation takes place. Benzene or other cyclic organic compound to bealkylated is introduced to alkylator ll via line I 8 which may enterunit I! at any suitable point therein. The alkylation eilluent is fedinto separator l9 where phase separation takes place. The organic phaseis passed via line 20 to fractionation unit 2| wherein is separated, forexample, a benzene recycle which is returned via line 22 to thealkylation zone, a fraction of unreacted HF which is recycled to theextraction step via lines 23 and I3 and a fraction of alkylated benzeneor other cyclic organic-compound withdrawn as bottoms product via line24.

The acid phase separated in unit I9 is withdrawn via line 25 andconventionally separated into two streams, one stream being recycled toextraction unit 5 via line 26 and the second, which should besufllciently large to keep the hydrofluoric acid in the system at thedesired level of purity, is passed via line 21 into column 8 wherein itis distilled together with the raflinate feed thereto via line a. Inthis way the hydrogen fluoride contained in this portion of the acidphase is recovered in purified form from the acidsoluble oils which arerecovered in admixture with the inert components of the raillnate vialine 28.

Example I To a refinery fraction comprising about 10 mol to a reactionvessel maintained at a temperature below about 80 to 90 F. by cold watercoils. The residence time in this vessel is about 10 to minutes. Thevessel is provided with a stirrer to prevent the separation of ahydrofluoric acid layer in the bottom. From this vessel the mix turepasses to another centrifugal-type mixer into which is introduced anadditional quantity of concentrated hydrofluoric acid approximatelyequal in volume to the total original propylenecontaining stream. Theresulting mixture passes to a centrifugal separator, from which theheavier or hydrofluoric acid phase is withdrawn and passes immediatelyto an alkylating zone. Into the alkylating zone is introduced benzene ina moi proportion about 5 to 10 times that of the original propylene. Thealkylation temperature is about 80 to 120 F.; the pressure, about 50 to150 p. s. i.; and the reaction time, about 5 to minutes. The eiliuentmixture from the alkylating zone is separated into an1acid layer whichis recycled to the two mixers mentioned hereinbefore, and a hydrocarbonphase which is further separated by fractional distillation intohydrofluoric acid and unreacted-benzene recycle fractions and into analkylate product fraction. The exact nature of the product dependssomewhat on the alkylation conditions, as is indicated by the followingillustrative data:

Run A B Temperature, E 118 118 Pressure. n. s. i 61 61 Contact time,min. 2o. 3 30. 9 Benzene/propylene, mol 8. 3 5. 4 Hydrocarbon/HF v0 l. 3l. 4 Benzene-free alkyiate:

Yield, Wt. per cent of oleiln 249 220 Olefin c ntent, Wt. per cent 0. 00. 0 Organic fluorine, Wt. per cent 0. 0005 0. 0004 Composition, vol.per cent lsopropylbenzene 93. 5 9i. 0 Diisflnropylbenzen 5. 5 8. 0Heavier l. 0 l. 0

Example If able dehydrogenation conditions, in a manner well-known tothe art. The resulting eilluent is cooled and is substantially freedfrom light gases. To it in liquefied condition is added hydrofluoricacid in a proportion approximately molecularly equivalent to thebutylene content. After a reaction period of about 10 to 15 minutes, theresulting mixture is rapidly countercurrently extracted withapproximately 0.2 to 0.3 times its own volume of additional liquidhydrofluoric acid, or, generally, with the minimal volume sufficient toremove substantially all of the tertiary butyl fluoride from themixture, whereby concomitant alkylation of isobutane is minimized. Theextract ls passed immediately to an alkylation zone at approximately thealkylation conditions cited in Example I, wherein it is intimatelyagitated with a several-fold molecular excess of benzene; additionalhydrofluoric acid is added, to increase the acid-to-hydrocarbon ratio toapproximately 1:1 by volume. The resulting mixture is then separatedinto two liquid layers, and the lower layer is recycled and/or purified.The upper layer is freed from acid and is then fractionally distilled toisolate the alkylate product boiling above benzene. Illustrative datafor this product are:

Yield, Wt. per cent of olefin 200 Olefin content, Wt. per cent 0.0Organic fluorine, Wt. per cent 0.0003 Composition, vol. per cent:

Tert-butylbenzene 92.0 Di-tert-butylbenzene 7.5 Heavier 0.5

The foregoing description is to be taken as illustrative only and not aslimiting the invention which is to be interpreted as limited solely bythe language of the appended claims.

I claim:

An improved process for reacting a lowboiling olefin and an alkylatablecyclic organic compound to produce alkyl derivatives of said cyclicorganic compound by replacement of hydrogen atoms on the ring with alkylgroups corresponding to said olefin in the presence of a hydrofluoricacid' catalyst, which comprises intimately admixing a hydrocarbonmaterial containing a low-boiling olefin with liquid hydrofluoric acidin an amount substantially equimolar to said olefin, maintaining saidadmixture for not more than about 30 minutes, intimately admixing withthe resulting material a substantial excess of liquid concentratedhydrofluoric acid as an extraction liquid in an extraction step at anextraction temperature not greater than about 100 F. and subsequentlyseparating a hydrocarbon phase and a first liquid hydrofluoric acidphase. intimately admixing an alkylatable cyclic organic compound withsaid liquid hydrofluoric acid extract phase under reaction conditionssuch as to efl'ect alkylation of said cyclic organic compound to producesaid alkyl derivatives thereof, separating eifluents of said reactioninto an organic phase and a second liquid hydrofluoric acid phase,recovering said alkyl derivatives of said cyclic organic compound fromsaid organic phase, passing a major portion of said second acid phase tosaid extraction step as a part of said extraction liquid, passing saidhydrocarbon phase to a distillation step for recovery of dissolvedhydrogen fluoride therefrom, passing a minor portion of said second acidphase to said distillation step for removal of organic impurities, andrecovering from said distillation step purified hydrogen fluoride andpassing same to said extraction step.

2. An improved process for reacting a low-boiling olefin and analkylatable aromatic hydrocarbon to produce alkyl derivatives of saidaromatic hydrocarbon by replacement of hydrogen atoms on the ring withalkyl groups corresponding to said olefin in the presence of ahydrofluoric acid catalyst, which comprises intimately admixing ahydrocarbon material containing a low-boiling olefin with liquidhydrofluoric acid in an amount substantially equimolar to said olefin,maintaining said admixture for not more than about30 minutes, intimatelyadmixing with the resulting material a substantial excess of liquidconcentrated hydrofluoric acid as an extraction liquid in an extractionstep at an extraction temperature not greater than about 100 F. andsubsequently separating a first hydrocarbon phase and a first liquidhydrofluoric acid phase, intimately admixing aromatic hydrocarbon withsaid liquid hydrofluoric acid phase under reaction. conditions such asto effect alkylation of said aromatic hydrocarbon to produce said alkylderivatives thereof, separating eiiiuents of said reaction into a secondhydrocarbon phase and a second liquid hydrofluoric acid phase,recovering said alkyl derivatives of said aromatic hydrocarbon from saidsecond hydrocarbon phase, passing a major portion of said second acidphase to said extraction step as a part of said extraction liquid,passing said first hydrocarbon phase to a distillation step for recoveryof dissolved hydrogen fluoride therefrom, passing a minor portion ofsaid second acid phase to said distillation step for removal of organicimpurities, and recovering from said distillation step purified hydrogenfluoride and passing same to said extraction step.

3. An improved process for reacting a low-boiling olefin and benzene toproduce alkyl derivatives of benzene by replacement of hydrogen atoms onthe ring with alkyl groups corresponding to said olefin in the presenceof a hydrofluoric acid catalyst, which comprises intimately admixingahydrocarbon material containing a low-boiling olefin with liquidhydrofluoric acid in an amount substantially equimolar to said olefin,maintaining said admixture for not more than about 30 minutes,intimately admixing with the resulting material a substantial excess ofliquid concentrated hydrofluoric acid as an extraction liquid in anextraction step at an extraction temperasubstantially equimolar to saidolefin, maintaining said admixture for not more than about minutes,intimately admixing with the resulting material asubstantial excess ofliquid concentrated hydrofluoric acid as an extraction liquid in anextraction step at an extraction temperature not greater than about 100F. and subsequently separating a first hydrocarbon phase and a firstliquid hydrofluoric acid phase, intimately admixing benzene with saidliquid hydrofluoric acid phase under reaction conditions such as toeffect alkylation of said benzene to produce said alkyl derivativesthereof, separating effluents of said reaction into a second hydrocarbonphase and a second liquid hydrofluoric acid phase, recovering said alkylderivatives of said benzene from said second hydrocarbon phase, passinga major portion of said second acid phase to said extraction step as apart of said extraction liquid, passing said first hydrocarbon phase toa distillation step for recovery of dissolved hydrogen fluoridetherefrom, passing a minor portion of said second acid phase to saiddistillation step for removal of organic impurities, and recovering fromsaid distillation step purified hydrogen fluoride and passing same tosaid extraction step.

4. An improved process for reacting a low-boiling olefin and iuran toproduce alkyl derivatives of furan by replacement of hydrogen atoms on-the ring with alkyl groups corresponding to said olefin in the presenceof a hydrofluoric acid catalyst, which comprises intimately admixing ahydrocarbon material containing a low-boiling olefin with liquidhydrofluoric acid in an amount ture not greater than about F. andsubsequently separating a hydrocarbon phase and a first liquidhydrofluoric acid phase, intimately admixing furan with said liquidhydrofluoric acid phase under reaction conditions such as to effectalkylation of said furan to produce said alkyl derivatives thereof,separating effluents of said reaction into an organic phase and a secondliquid hydrofluoric acid phase, recovering said alkyl derivatives ofsaid furan from said organic phase, passing a major portion of saidsecond acid phase to said extraction step as a part of said extractionliquid, passing said hydrocarbon phase to a distillation step forrecovery of dissolved hydrogen fluoride therefrom, passing a minorportion of said second acid phase to said distillation step for removalof organic impurities, and recovering from said distillation steppurified hydrogen fluoride and passing same to said extraction step.

5. An improved process for reacting propylene 'with an alkylatablecyclic organic compound to produce propyl derivatives of said cyclicorganic carbon material containing propylene and propane with liquidhydrofluoric acid in an amount substantially equimolar to saidpropylene, maintaining said admixture for not more than about 30minutes, intimately admixing with the resulting material a substantialexcess of liquid concentrated hydrofluoric acid as an extraction liquidin an extraction step at an extraction temperature not greater thanabout 100 F. and subsequently separating a hydrocarbon phase and a firstliquid hydrofluoric acid phase, intimately admixing an alkylatablecyclic organic compound with said liquid hydrofluoric acid phase underreaction conditions such as to efi'ect alkalation of said cyclic organiccompound to produce said propyl derivatives thereof, separatingeiiluents of said reaction into an organic phase and a second liquidhydrofluoric acid phase, recovering said propyl derivatives of saidcyclic organic compound from said organic phase, passing a major portionof said second acid phase to said extraction step as a part of saidextraction liquid, passing said hydrocarbon phase to a distillationstepfor recovery of dissolved hydrogen fluoride therefrom, passing a minorportion of said second acid phase to said distillation step for removalof organic impurities, and recovering from said distillation steppurified hydrogen fluoride and passing same to said extraction step.

6. An improved process for reacting propylene with benzene to producepropyl derivatives of said benzene by replacement of hydrogen atoms onthe ring with propyl groups which comprises intimately admixing anormally gaseous hydrocarbon material containing propylene and propanewith liquid hydrofluoric acid in an amount substantially equimolar tosaid propylene, maintaining said admixture for not more than about 30minutes, intimately admixing with the resulting material a substantialexcess of liquid concentrated hydrofluoric acid as an extraction liquidin an extraction step at an extraction temperature not greater thanabout 100 F. and subsequently separating a first hydrocarbon phase and afirst liquid hydrofluoric acid phase, intimately admixing benzene withsaid liquid hydrofluoric acid phase under reaction conditions such as toeflect alkylation of said benzene to produce said propyl derivativesthereof, separating efliuents of said reaction into a second hydrocarbonphase and a second liquid hydrofluoric acid hase, recovering said propylderivatives of said benzene from said second hydrocarbon phase, passinga major portion of said second acid phase to said extraction step as apart of said extraction liquid, passing said first hydrocarbon phase toa distillation step for recovery of dissolved hydrogen fluoridetherefrom, passing a minor portion of said second acid phase to saiddistillation step for removal of organic impurities, and recovering fromsaid distillation step purified hydrogen fluoride and passing same tosaid extraction step.

7. An improved process for reacting propylene with iuran to producepropyl derivatives of said furan by replacement of hydrogen atoms on thering with propyl groups which comprises intimately admixing a normallygaseous hydrocarbon material containing propylene and propane withliquid hydrofluoric acid in an amount substantially equimolar to saidpropylene, maintaining said admixture for not more than about 30minutes, intimately admixing with the resulting material a substantialexcess of liquid concentrated hydrofluoric acid as an extraction liquidin an extraction step at an extraction temperature not greater thanabout 100 F. and subsequently separating a hydrocarbon phase and a firstliquid hydrofluoric acid phase, intimately admixing furan with saidliquid hydrofluoric acid phase under reaction conditions such as toeffect alkylation of said furan to produce said propyl derivativesthereof, separating eflluents of said reaction into an organic phase anda second liquid hydrofluoric acid phase, recovering said propylderivatives of said furan from said organicphase, passing a majorportion of said second acid phase to said extraction step as a part ofsaid extraction liquid, passing said hydrocarbon phase to a distillationstep for recovery of dissolved hydrogen fluoride therefrom, passing aminor portion of said second acid phase to said distillation step forremoval of organic impurities, and recovering from said distillationstep purified hydrogen fluoride and passing same to said extractionstep.

8. An improved process for reacting isobutylene and an alkylatablecyclic organic compound to produce tertiary butyl derivatives of saidcyclic organic compound by replacement of hydrogen atoms on the ringwith tertiary butyl groups in the presence of a hydrofluoric acidcatalyst, which comprises intimately admixing a normally gaseoushydrocarbon containing isobutylene and isobutane in liquid phase withliquid hydrofluoric acid in an amount substantially equal to thebutylene content of said hydrocarbon, maintaining said admixture for notmore than about-30 minutes, intimately admixing with the resultingmaterial a substantial excess of liquid concentrated hydrofluoric acidas an extraction liquid in an extraction step at an extractiontemperature not greater than about 100 F., subsequently separating ahydrocarbon phase and a first hydrofluoric acid phase, intimatelyadmixing an alkylatable cyclic organic compound with said liquidhydrofluoric acid phase under reaction conditions such as to eflectalkylation of said cyclic organic compound to produce tertiary butylderivatives thereot, separating emuents of said reaction into an organicphase and a second liquid hydrofluoric acid phase, and recovering saidtertiary butyl derivatives of said cyclic organic compound from saidorganic phase.

9. An improved process for reacting isobutylene and benzene to producetertiary butyl derivatives of benzene by replacement of hydrogen atomson the ring with tertiary butyl groups in the presence of a hydrofluoricacid catalyst, which comprises intimately admixing a normally gaseoushydrocarbon containing isobutylene and isobutane in liquid phase withliquid hydrofluoric acid in an amount substantially equal to thebutylene content of said hydrocarbon, maintaining said admixture for notmore than about 30 minutes, intimately admixing with the resultingmaterial a substantial excess of liquid concentrated hydrofluoric acidas an extraction liquid in an extraction step at an extractiontemperature not greater than about 100 F., subsequently separating afirst hydrocarbon phase and a first liquid hydrofluoric acid phase,intimately admixing benzene with said first liquid hydrofluoric acidphase under reaction conditions such as to effect alkylation of benzeneto produce tertiary butyl derivatives thereof, separating efliuents ofsaid reaction into a second hydrocarbon phase and a second liquidhydrofluoric acid phase, and recovering said tertiary butyl derivativesof benzene from said second hydrocarbon phase.

10. An improved process for reacting isobutylene and furan to producetertiary butyl derivatives of furan by replacement of hydrogen atoms onthe ring with tertiary butyl groups in the presence of a hydrofluoricacid catalyst, which comprises intimately admixing a normally gaseoushydrocarbon containing isobutylene and isobutane in liquid phase withliquid hydrofluoric acid in an amount substantially equal to thebutylene content of said hydrocarbon, maintaining said admixture for notmore than about 30 minutes, intimately admixing with the re-.

sulting material a substantial excess of liquid concentratedhydrofluoric acid as an extraction liquid in an extraction step at anextraction temperature not greater than about 100 F., subsequentlyseparating a hydrocarbon phase and a first hydrofluoric acid phase,intimately admixing furan with said liquid hydrofluoric acid phase underreaction conditions such as to efiect alkylation of furan to producetertiary butyl derivatives thereof, separating eiiiuents of saidreaction into an organic phase and a second liquid hydrofluoric acidphase, and recovering said tertiary butyl derivatives of furan from saidorganic phase.

11. The process of claim 8 wherein higher isoparamn formed in saidextraction step by alkylation 01' isobutane and appearing in saidhydrocarbon phase is separately recovered by passing said hydrocarbonphase to a distillation zone and there separating said higherisoparaflin from the isobutane and hydrogen fluoride, and wherein saidisobutane and hydrogen fluoride so recovered are recycled to saidextraction step.

12. A process for reacting a low-boiling aliphatic olefin and analkylatable cyclic organic compound to produce alkyl derivatives of saidcyclic organic compound by replacement of hydrogen atoms on the ringwith alkyl groups corresponding to said olefin which comprisesintimately admixing a hydrocarbon material containing said olefin andthe corresponding paraflln with liquid hydrofluoric acid in amountsubstantially equimolar tosaid olefin, maintaining the resulting mixtureunder conditions efiecting substan- 13. tially completehydrofluorination of said oleflns as substantially the sole reaction,extracting the resulting mixture with sufilcient liquid hydrofluoricacid to form a separate liquid phase under conditions such thatsubstantially complete extraction of the alkyl fluorides in said liquidof said cyclic organic compound from the alkylation eflluent. v

13. The process of claim 12 wherein said cyclic organic compound isintroduced to said alkylation step in 8. mol proportion of from .totimes that of the alkyl fluoride present.

14. The process of claim 12 wherein said corresponding paraflin is anisoparaflin, wherein substantial alkylation thereofin saidhydrofluorination step is avoided, and wherein alkylation thereof insaid extraction step is minimized.

15. The process of claim 8 wherein said extraction step is conducted asa liquid-liquid extraction at a temperature not greater than about 100F. and with the amount of separate liquid hydrofluoric acid phaseranging from approximately 0.2 to 0.3 times the volume of thehydrocarbon phase. a

14 16. The process of claim 12 wherein said extraction step is conductedas a liquid-liquid extraction at a temperature not greaterthan about F.and with the amount of separate liquid hydrofluoric acid phase rangingfrom approximately 0.2 to 0.3 times the volumeof the hydrocarbon phase.

1'7. The process which comprises alkylating furan with a lower alkylfluoride in the presence of liquid substantially anhydrous hydrofluoricacid as the catalyst.

18. The process which comprises alkylating an alkylatable organiccompound having a fivemembered heterocyclic ring with an alkyl fluoridein the presence of liquid hydrofluoric acid as a catalyst.

19. A process which comprises alkylating an presence of hydrofluoricacid as a catalyst.

MARYAN P. MATUSZAK.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,387,162 Matuszak pct. 16, 1945

